emacs lisp syntax rfc: (cond (EXPR => (lambda (X) ...)))

From:

Thien-Thi Nguyen

Subject:

emacs lisp syntax rfc: (cond (EXPR => (lambda (X) ...)))

Date:

Sun, 02 Jan 2011 22:45:56 +0100

User-agent:

Gnus/5.13 (Gnus v5.13) Emacs/24.0.50 (gnu/linux)

In Scheme, the expression:
(cond (EXPR => (lambda (X) ...)))
provides the lambda expression parameter X with the non-false
value computed from evaluating EXPR. However, if EXPR evaluates
to false, control falls through to the next ‘cond’ clause, as
usual. The syntax requires the symbol ‘=>’ between EXPR and the
lambda expression, without which the non-false value is discarded
(i.e., the status quo).
What do people think of adding this to Emacs Lisp? (I would be
grateful for pointers to any previous discussion on the matter.)